gms | German Medical Science

122. Kongress der Deutschen Gesellschaft für Chirurgie

Deutsche Gesellschaft für Chirurgie

05. bis 08.04.2005, München

Human guanylate binding protein-1: a novel serological marker of inflammatory blood vessel activation

Meeting Abstract

  • corresponding author M. Stürzl - Department of Surgery, Division of Molecular and Experimental Surgery, University of Erlangen-Nürnberg
  • M. Bauer - Department of Surgery, Division of Molecular and Experimental Surgery, University of Erlangen-Nürnberg
  • E. Naschberger - Department of Surgery, Division of Molecular and Experimental Surgery, University of Erlangen-Nürnberg
  • W. Hohenberger - Department of Surgery, Division of Molecular and Experimental Surgery, University of Erlangen-Nürnberg
  • E. Guenzi - GSF-National Research Center for Environment and Health, Department of Virus-induced Vasculopathy
  • C. Lubeseder-Martellato - GSF-National Research Center for Environment and Health, Department of Virus-induced Vasculopathy

Deutsche Gesellschaft für Chirurgie. 122. Kongress der Deutschen Gesellschaft für Chirurgie. München, 05.-08.04.2005. Düsseldorf, Köln: German Medical Science; 2005. Doc05dgch2963

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/dgch2005/05dgch570.shtml

Veröffentlicht: 15. Juni 2005

© 2005 Stürzl et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Introduction

Recently we identified the large GTPase human guanylate binding protein-1 (GBP-1) as the key mediator of the anti-angiogenic effects of inflammatory cytokines (IC) on endothelial cells (EC). Endothelial GBP-1 expression is induced by the IC interferon (IFN)-α and -γ, tumor necrose factor-α (TNF-α) and interleukin (IL)-1 and is inhibited by the angiogenic growth factors vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). At the tissue level, GBP-1 expression is highly associated with EC and specifically found in IC-activated EC, as demonstrated by immunohistochemical studies in tissue sections from skin diseases with a prominent inflammatory component, e.g. Kaposi´s sarcoma, psoriasis and adverse drug reaction. The highly specific expression of GBP-1 in IC-activated EC is regulated by a ISRE-NFκB promoter module. Preliminary analysis of the promoter revealed that this IC-response modul may be more sensitive to IC in EC as compared to other cell types.

Materials

GBP-1 was immunoprecipitated from cell culture supernatants of untreated and IFN-γ-stimulated HUVEC with a specific polyclonal antibody and analysed by Western blot. Cell death was determined by lactate dehydrogenase activity assay to ensure that GBP-1 was not released due to unspecific cell leakage. A GBP-1-specific sandwich ELISA was developed to quantify GBP-1 levels in cell culture supernatants and body fluids. Serial dilutions of recombinant His-tagged human GBP-1 were used as standard.

Results

Here we show that IFN-γ-stimulated EC secrete GBP-1 into the culture medium. This was not due to unspecific protein release by cell death and occurred despite the absence of a leader peptide. GBP-1 secretion was insensitive to monensin and brefeldin A, but was selectively inhibited by glyburide and BSP. These two drugs are known to interfere with the non-classical protein secretion pathway that is mediated by ABCA1, a member of the ATP-binding cassette transporter proteins. Using a newly developed ELISA increased concentrations of soluble GBP-1 could be detected in the sera of patients with Morbus Crohn [median concentration 46,9 ng/ml (n=20) vs 17,8 ng/ml in control group (n=24)] and in the liquor of patients with bacterial meningitis [196,2 ng/ml (n=7) vs 1,2 ng/ml in control (n=7)].

Discussion

In summary our data indicate that GBP-1 may serve as a novel serological marker to specifically detect inflammatory activation of blood vessels in inflammatory diseases.